Lamp unit



A. G. FOOTE Nov. 26, 1946.

LAMP UNIT Filed April 23, 1943 lnven tov AL't'on G. Foo+e,

His A't'torne Patented Nov. 26, 1946 LAMPUNIT Alton G. Foote, Wlcklifle,Ohio, assignor to General Electric Company, a corporation of New YorkApplication April 23, 1943, Serial No. 484,211

9 Claims. (01. 176-32) My invention relates in general to a lamp unit 1comprising a plurality of individual lamp ele- 'ments mounted in acommon base or holder.

' More particularly, my invention relates to a base or holderconstruction for such lamp units.

' As a means for denoting the variation in the oxygen content of thehuman blood stream, it has been proposed to direct a beam of lightthrough a membraneous portion of the human anatomy such as the ear, andonto the light-sensitive element of a photoelectric cell connected tosuitable indicator means. The current generated by the excitedphotoelectric cell actuates the indicator means to thereby give a readyindication of the oxygen content of the bloodstream. Inasmuch as thelight transmission of the blood stream varies in accordance with theoxygen content thereof, the light reaching the photoelectric cell, andtherefore the magnitude of the current generated thereby, will vary inproportion to such oxygen content. Accordingly, the indicator meanscontrolled by the photoelectric cell will give a reading as determinedby the light transmission, and therefore the oxygen content of the bloodstream. Such blood stream oxygen content-indicating devices are ofparticular util ity as oxygen want indicators in cases where one is tobe exposed to regions of rarified atmosphere and for that reason hasequipped himself with suitable means for supplying his respiratorysystem with additional oxygen from an artificial source thereof. Bymeans of the oxygen want indicator, such person is immediately informedof any falling-oil in the oxygen con- .tent of his blood stream and.therefore, oi the nfed 01' additional oxygen from the artificial sup- Py- As the source of the light beam for such oxygen want indicators, ithas been proposed to employ a lamp. unit comprising a plurality ofminiature flashlight lamps mounted in a common base or holder member,the lamp unit being so constructed as to fit against the head of a humanbeing at a point immediately behind the ear'of such person. It is anobject of the present invention to provide such a lamp unit which issimple in construction and which can be man-.

ufactured without the need of any ligsfor holding the several lampelements in proper relation with one another while they are beingsecured in place in the common base or holder member.

Further objects and advantages of my inven tion will appear from thefollowing description of a species thereof and from the accompanying 2drawing in which Fig. l is a plan view on an enlargedscale of a lampunit comprising my invention; Fig. 2 is a longitudinal section of thelamp unit shown in Fig. 1; Fig. 3 is a section on the line 3-3 of Fig.2; and Fig. 4 is a section on the line 4-4 of Fig. 2.

Referring to the drawinggthe lamp unit there shown comprises aplurality, preferably four,of lamp elements Ill mounted in a common baseor holder II. The lamp elements are of the type shown in Fig. 2 ofUnited States Patent No. 1,983,362 issued December-i, 1934, to Geiger etal., each of. said lamp elements comprising a. small cylindrical glassbulb l2 formed with an integral double-convex lens I 3 at its tip endand with an annular enlarged or protuberant portion M at an intermediatepointthereof. Disposed within and butt-sealed into the bulb i2 is a saidwires. The innermost ends I! of said leading-in wires l5 are bentoutwardly at an angle, the said endsbeing located a definitepredetermined distance from the surface I8 of the bead IS. A filamentl9, preferably in the form of a linear coil of tungsten or othersuitable refractory metal, is mounted on the leading-in wires l5 atapoint intermediate the inner ends ll thereof and the bead Hi, the saidfilament being.

located at a predetermined distance from the surface I! of the bead Hi.The leading-in wires ii are sealed through the wall of the bulb l2 atdiametrically opposite points thereof and are formed with outer endportions for connection to a source of electric current. The mountstructure is butt-sealed into the lamp bulb I! so that the outwardlybent inner ends I! of the leading-in wires l5 engage the inner surfaceof the lens portion I: of the bulb. Since the tile.- ment l9 bears adefinite relationship to the ends I! of the leading-in wires (both beinglocated definitely with respect to. the surface l8 of the bead It), thesaid filament is therefore located in a definite predeterminedrelationship to the lens l3. By means of this construction, theleading-in wires and filament are fixedly supported with reference tothe lens l3 throughout the life of the lamp, the said lens serving todirect the light rays from the filament into a more or less concentratedbeam.

In accordance with the invention, the base or holder H for the severallamp elements-l0 comprises an elongated arcuate-shaped casing or aunseshousing 2| formed of insulating material and divided longitudinally intoa pair of complementary halves or sections 22, 23 which are heldtogether in assembled relation by suitable fastening means, such as apair of rivets 24. The casing 2| is preferably made of a suitableplastic material such as that commonly known as Textolite," forinstance. The several lamp elements ID are mounted in the base casing 2|in a row therealong and with just the tip or lens portions I3 of thelamp elements projecting above the upper surface 25 of the casing.

As shown in Figs. 1 and 2, the casing 2| is longitudinally curved in twoplanes at right angles to one another.- Referring to Fig. l, the casing2| is curved in an are about an axis A extending transversely of thecasing and parallel to the front and rear sides 26, 21 thereof, the wfront side 26 having the convex curvature and the rear side 2'! theconcave curvature. The lamp elements In are mounted in the casing 2| inan arc corresponding in curvature to the curvature of the casing aboutthe axis A. The concavity of the rear side 21 of the casing is such asto enable the said rear side to more or less fit against that portion ofa person's head just be hind the ear with the row of lamp elements Idisposed adjacent and extending along the rear side of the car. A radiusof curvature n of about 1% inches for the rear side 21 of the casing hasbeen found to be more or less suitable for such purpose.

To produce a convergence of the lightbeams projected by the row of lampelements ill, the casing 2| is also curved, and the lamp elements l0 aredisposed, in corresponding arcs about an axis B (Fig. 2) extendingtransversely of the casing and parallel to the upper surface 25 of thecasing, the said upper surface 25 having the concave curvature. Becauseof such longitudinal arcuate disposition of the lamp elements ill in thecasing 2| about the axis B, the axes of the said lamp elements, and thusthe light beams I and snugly receive cylindrical wall portions of thelamp bulbs l2 adjacent each side of the annular protuberant portions l4thereof. In addition, the said sockets are provided with annularenlargements or cavities 32 located entirely within the body of thecasing or holder 2| and shaped to conform to and snugly receive theannular protuberant portions i4 of the lamp bulbs l2.

As shown in Fig. 2, the outer leads 23 of the lamp elements III areinterconnected, as by solof matching recesses 34 in the opposed faces23,

of the two casing sections 22, 23.

The external connection'for the lamp elements I0 is provided by theconnection, as by soldering,

of each of the base fastening rivets 24 to one of the outer leads 20 ofthe lamp elements In at each end of the base'casing 2|, the said rivetsthus serving both as a fastening means and as the terminal contacts forthe base. For this purpose, the rivets 24 are formed with extensionsprojected thereby, will therefore converge along the axis B oflongitudinal curvature. The curvature of the longitudinal arcuatedisposition of the lamp elements i0 about the axis B is preferably suchas to cause the light beams from the lamp elements ID to be concentratedsubstantially into the full pick-up" area of the photoelectric cell (notshown) with which the lamp unit is to be used. In the instance shown, aradius 12 of around 1% inches has been found to be satisfactory for theradius of curvature of the longitudifnal arcuate disposition of the lampelements l about the axis B, as measured from the exposed tips thereof.4

For supporting the lamp elements ill in place within the casing 2 I, thetwo interengaging faces 23, 30 of the casing sections 22, 23 are formedwith a plurality of corresponding recesses 3| at spaced pointstherealong, which recesses match with one another, when the two sectionsare assembled, to thereby form individual sockets or chambers for thelamp elements. The said recesses 3|, and therefore the lamp-receivingchambers formed thereby, are shaped to conform substantially to theconfiguration of, and completely enclose the annular protuberant portionH of, the lamp bulbs I2 so that the several lamp elements Ill-snugly fitwithin the said chambers and are firmly retained and supported in placewithin the casing 2|. As shown in Figs. 2 and 4, the lamp sockets formedby the matching recesses 2| are of cylindrical shape to conform to 3which project laterally from the convex front side 26 of the casing 2|to thereby constitute terminal posts or prongs. The rivets 24 extendthrough openings 36 in the casing sections 22, 23 and into thepassageway 33 in the casing to thereby enable the soldering of the outerleads 2|) of the end lamp elements ill to the said rivets during theassembly of the lamp unit. Instead of utilizing the rivets 24 both asthe base fastening means and as the terminal contacts for the lamp unit,separate terminal contact members may be provided instead and the rivets24 then utilized solely as a base fastening or assembly means.

After the lamp elements l0 have been inserted in place in the recesses3| in the front section 22 of the base casing 2| and the various lampleads 20 have been properly connected to one another and to the basefastening rivets 24, the rear section-23 of the base casing is thenfitted in place against the front section 22 thereof and the twosections riveted together by peaning over the hollow rear end of eachrivet 24' to form a head 31. The holes 36 in the casing through whichthe rivets 24 extend are countersunk at the rear side of the casing, asshown at 38 in Fig. 3, to thereby provide enlarged recesses for thecomplete accommodation therein of the rivet heads 31.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A lamp unit comprising a plurality of lamp elements,'a common holderfor said lamp elements comprising a pair of complementary sections,terminal contact members on said holder shaped to engage a currentsupply connector, and conductor means connecting said lamp elements tosaid terminal contact members, said terminal contact members also beingconstructed and arranged to hold said sections in assembled relationwith said lamp elements clamped therebetween so as to be firmly held inplace in said holder.

2. A lamp unit comprising a plurality of lamp elements, a common holderfor said lamp elements comprising a pair of complementary sections,fastening means for holding said sections together with the lampelements clamped therebetween and firmly held in place in said holder,said fastening means being provided. with prongshaped extensionsprojecting outwardly of said holder to serve as terminal contacts, andconductor means connecting said lamp elements to said fastening means.3. A lamp unit comprising a plurality of lamp elements each comprising acylindrical glass bulb having an integral intermediate annularprotuberant portion, a common holderfor said lamp elements comprising apair of complementary sections having abutting faces provided withmatching lamp-receiving recesses which together form sockets for thelamp elements and include enlarged portions shapedto snugly receive theannular protuberant portions of said lamp bulbs, and fastening means forholding said sections together with said lamp elements clampedtherebetween so as to be firmly held in place in said holder within thesaid sockets therein.

4. A lamp unit comprising a plurality of lamp elements each comprisinga. cylindrical glass bulb having an integral intermediate annularproturberant portion, a common holder for said lamp elements comprisinga pair of complementary sections having abutting faces provided withmatching identical lamp-receiving recesses which together form socketsfor mounting the lamp elements within said holder, said sockets being ofcylindrical shape to conform to and receive the cylindrical wallportions of the lamp bulbs,

and each of said sockets having an annular enlargement located withinthe body of said holder and shaped to conform to and receive the annularprotuberant portions of the lamp bulbs, and fastening means.,for holdingsaid sections together with said lamp elements clamped therebetween soas to be firmly held in place in said holder within the said socketstherein.

5. A miniature lamp unit sufficiently small to fit behind a persons earcomprising a plurality of miniature lens-end lamp elements, a commonholder for said lamp elements comprising an elongated housing ofinsulating material divided longitudinally into two complementarysections, said housing being of arcuate shape in two planeslongitudinally thereof so as to have a concave upper surface and aconcave inner side and a convex outer side, said sections being providedat spaced points therealong with matching lamp-receiving recesses intheir abutting faces aligned to' form sockets having their axesconvergently directed to a common focus the lamp elements mounted insaid sockets in said holder with the lens ends thereof projecting fromthe concave upper surface of said holder and with the lamp elementsinclined toward one another so as to concentrate the light beamsemanating from the lens ends of said lamp elements, and fastening meansfor holding said sections together with the lamp elements clampedtherebetween so as to be firmly held in place in 'saidholder within thesaid recesses therein.

6. A lamp unit comprising a plurality of 6 elongated housing ofinsulating material divided longitudinally into two complementarysections, said housing being of arcuate shape in two planeslongitudinally thereof so as to have a concave upper surface and aconcave inner side and a convex outer side, said sections being providedat spaced points therealong with matching lampreceiving recesses intheir abutting faces for mounting the lamp elements in said holder withthe lens ends thereof projecting from the concave upper surface of saidholder and with the lamp elements inclined toward one another so' as toconcentrate the lightbeams emanating from the lens ends of saidlampelements, fastening means for holding said sections together with thelamp elements clamped therebetween so as to be firmly held in place insaid holder within the said recesses therein, said fastening meanscomprising a pair of elongated metal members extending laterally throughsaid housing and having their inner ends terminating inwardly of theconcave inner side of said housing and their outer ends formed withprong-shaped extensions projecting from the convex outer side of saidhousing to serve as terminal contacts for the lamp unit, and conductormeans within said housing connecting said lamp elements to saidfastening members.

7. A miniature portable lamp unit comprising an elongated holder dividedlongitudinally into sections having complementary laterally extendingrecesses arranged in a row along the length of the holder and aligned toform sockets and also having a pair of longitudinally extendingcomplementary recesses forming a channel communicating with the socketsat their inner ends, a row of baseless miniature electric lamps disposedin said sockets and having lead wires extending therefrom into saidchannel with the lead wires of adjacent lamps mechanically andelectrically connected together, and fastening means clamping saidholder sections together and retaining said lamps therein.

8. A miniature portable lamp unit comprising an elongated holder dividedlongitudinally into sections having complementary laterally extendingrecesses arranged in a row along the length of the holder and aligned toform sockets, the axes of said sockes being convergently directed towarda common focus, a row of miniature electric lamps disposed in saidsockets, and fastening means clamping said holder sections together andretaining said lamps therein.

9. A miniature portable lamp unit comprising an elongated holder dividedlongitudinally into sections having complementary laterally extendingrecesses arranged in a row along the length of the holder and aligned toform sockets, the axes of said sockets being convergently directedtoward a common focus, a row of miniature electric lamps disposed insaid sockets and having lenses at their ends for concentrating the lighttherefrom on said common focus, and fastening means clamping said holdersections together and retaining said lamps therein.

ALTON G. FOO'IE.

